The present invention relates to flotation collars and in particular to a flotation collar which ensures auto-rotation of a wearer, either conscious or unconscious, and that the head of the wearer is carried above the water
Military requirements and specifications, and Federal regulations require the presence of life preservers on board ships and on aircraft for use in the event of a water crash, ditching, ejection, or other event over water or in water. Crew members and passengers who may be required to use such life preservers may further desire features to enhance the reliability, operation, and ease of use of life preservers. In some instances, life preservers may be positioned at various locations around a ship, and donned only for drills or actual emergencies. In other cases, for example in military aircraft flown over water, inflatable flotation collars are worn while operating an aircraft.
U.S. Pat. No. 1,385,581, U.S. Pat. No. 2,210,809, and U.S. Pat. No. 5,421,760 disclose flotation devices residing about a wearer's neck. The resulting buoyancy carries the wearer face forward in the water in a somewhat vertical position. Swimming while thus positioned, especially for long distances, is difficult and exhausting.
Newer flotation collars extend below the neck, and thus lift more of the wearer's torso. Many of these newer flotation collars also include at least two chambers to provide redundancy. Unfortunately, multiple chambers may result in unstable support if one of the air compartments (or cells) fails. U.S. Pat. No. 5,692,933 describes a flotation collar having two symmetric cells within a fabric shell, either of which cells is able to support a wearer. Unfortunately, the flotation collar described in the '933 patent is somewhat bulky, and may limit the wearer's motion. Such limiting is often undesirable, for example, for a pilot.